Thermal treatment of dispersible raw material with riser tubes takes place, for example, in the calcination of cement raw material in the production of cement clinker. The thermal energy that is required therefor is provided by fuel which is combusted in a separate combustion chamber that is connected to the riser tube, for example (DE 10 2004 045 510 A1). A similar concept is known from DE 195 35 312 A1 which discloses a reactor, linked to the exhaust line, for generating a combustible gas from waste materials, in particular from old tires. The reactor herein is configured as a gasification reactor and by way of a tertiary air line is connected to the cooler of a cement-clinker system in such a manner that at least a part of the exhaust air of the cooler is useable as a gasification means in the reactor. According to DE 10 2005 052 753 A1, the additional combustion region is configured as underfeed combustion.
In the case of all these variously configured combustion chambers, hot exhaust air of the cooler is utilized for reacting the fuel, wherein the hot gases being created are fed to the calcinator. Raw meal is employed herein for regulating the temperature. These concepts have the disadvantage of a high complexity in terms of apparatuses, this being associated with feeding the hot exhaust air of the cooler and the raw meal by way of separate lines. In many existing systems, the meal feed in particular prevents the technology from being retrofitted, since there is no adequate height differential in order for the raw meal to be able to be fed by means of gravity.
By contrast, WO 2012/048159 A2 pursues another concept in which solid fuel, for example old tires, is combusted directly in the riser tube by means of a pivotable mounting installation. While this method does have the advantage that the complexity in terms of apparatuses relating to the tertiary air lines may be correspondingly reduced, a correspondingly high complexity for the mounting device due to the extremely high temperatures does have to be taken into account.